1. Field
Nanocrystal-polymer composites and production methods thereof are disclosed.
2. Description of the Related Art
Unlike emissive displays such as a plasma display panel (PDP) and a field emission display unit (FED), liquid crystal displays (LCDs) are non-emissive display units that cannot emit light by themselves and require incident light from outside to form an image. Therefore, the LCD has a backlight unit that is located at its rear side so as to emit light.
The backlight unit for the LCD used a cold cathode fluorescent lamp (CCFL) as a light source. However, using the CCFL has disadvantages in that uniform brightness may not be ensured and color purity may decrease as the size of the LCD becomes larger.
In recent years, a backlight unit using a three color LED as a light source has been developed. The unit may reproduce high color purity and thus may find utility in a high quality display unit. However, the backlight unit using the three color LED is far more expensive than the CCFL, and in order to overcome such drawback, many researchers have focused on developing a white LED that may convert light from a single color LED chip to output white light.
The white LED may secure profitability, but it has disadvantageously poor color purity and a low level of color reproducibility in comparison with the three color LED. Accordingly, attempts have been made to use semiconductor nanocrystals as a material for a light converting layer in the LED in order to enhance color reproducibility and color purity and to have price competitiveness.